1. Field of the Invention
The present invention relates to a method of producing a piezoelectric/electrostrictive film type device provided with a substrate formed with a cavity and a vibrating laminate obtained by laminating electrode films and a piezoelectric/electrostrictive film which are aligned with the plane position of the cavity, on a first principal surface of the substrate.
2. Description of Related Art
FIGS. 58A to 58C are schematic sectional views for describing a conventional method of producing a piezoelectric/electrostrictive film type device 9 constituting the essential part of an ink jetting piezoelectric/electrostrictive actuator to be used for the head of an ink jet printer.
In the conventional production method, as shown in FIG. 58A, a conductive material paste is applied by screen printing to the surface of a substrate 902 formed with a cavity 926 which is to be an ink pressure room and the obtained coating film is fired into a lower electrode film 912. Thereafter, as shown in FIG. 58B, a piezoelectric/electrostrictive material paste is applied by screen printing to the lower electrode film 912 and the obtained coating film is fired into a piezoelectric/electrostrictive film 914. Then, as shown in FIG. 58C, an electroconductive material paste is formed by screen printing on the piezoelectric/electrostrictive film 914 and the obtained coating film is fired into an upper electrode film 916.
Japanese Patent No. 3999044 discloses a method of producing an ink jetting piezoelectric/electrostrictive actuator to be used for the head of an ink jet printer.
However, the conventional production method has the problem that pores are increased in the lower electrode film by the firing performed after the lower electrode film is formed, leading to a reduction in the coating ratio of the lower electrode film. This problem is particularly significant when the film thickness of the lower electrode film is reduced to increase the amount of displacement of flexure.
In addition, the conventional production method has the problem that the plane position of the lower electrode film is deviated from the plane position of the cavity by a dimensional variation and deformation of the substrate and screen plate, causing a variation in the amount of ink to be jetted from the piezoelectric/electrostrictive actuator.
These problems are common not only to a piezoelectric/electrostrictive film type device constituting the essential part of the piezoelectric/electrostrictive actuator but also to a piezoelectric/electrostrictive film type device provided with a substrate formed with a cavity and a vibrating laminate obtained by laminating an electrode film and a piezoelectric/electrostrictive film which are aligned with the plane position of the cavity, on the surface of the substrate, such as a film bulk acoustic resonator (FBAR) having a diaphragm structure.